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Rice bacterial rot is caused by Erwinia chrysanthemi (Erwinia chrysanthemi pv.zeae) a bacterial rice diseases in recent years occurred in the southern rice-producing areas in China more serious diseases, from the late 1990s to the present area, occurred gradually spread gradually increasing rice hazards. Rice bacterial rot in Hubei Province in July 2009, in Yangxin, Zhijiang, Daye, Dangyang other cities and counties for the first time occurred on the Hubei rice production caused very large losses. In the investigation based on the occurrence of hazards of pathogen, the pathogen preliminary study, and several chemicals were measured effect of the indoor virulence of pathogens. Expectations-oriented to disease further basic research and prevention to lay the foundation, the study's main results are as follows: 1. Displayed on the incidence of plant yield monitor results, the impact of the disease on rice yield mainly the diseased empty blighted rate increase, lower seed setting rate. Compared with healthy plants, blighted rate increased 3.5 times, a 26% reduction in seed setting rate, the general yield losses of about 40%, re-diseased plants up to 60%, up to 90% or more serious. 2. Tissue isolation and diluted separation from the incidence of rice isolated 21 strains of bacteria through express fast detection kit, NGM medium identification, specific primers identification and ribosomal DNAITS Sequence Identification separate 21 strains were identified, the finalization of the six strains of Erwinia chrysanthemi bacterial genera such as Erwinia chrysanthemi, respectively named Echl-01 Ech2-01-02 Ech2 Ech2-03, Ech3-01, Ech3- 02.3 Pathogenicity Test results showed that acupuncture and injection of stem base can cause the typical symptoms, leaves vitro inoculation with live body spray vaccination did not have any symptoms, and speculated that bacteria can not from blades infection caused by occurrence of disease; bacteria may from the wound, the injured leaf sheath and root intrusion, so easily lead to the prevalence of the disease after heavy rain flooded. Which invade wounds from the root, stem base, can also invade the seed germination process, reduce the rate of seed germination, cause bud rot, rot. 4. The base rot germs separated Bai Yang, Zhijiang, Daye Gram staining, capsule staining, starch hydrolysis, methyl red (MR), catalase, gelatin liquefaction, indole test pectin decomposition, lecithin, enzymes and the determination of the physiological and biochemical properties, similar to the results with other strains. Temperature tests to determine the strain of separation from the Hubei Province optimum growth temperature is 28 ~ 32 ℃, the lowest growth temperature of 10 ° C, the highest growth temperature of 41 ° C, the lethal temperature is between 53 ~ 54 ℃. pH test results show that isolated from Hubei around the Erwinia chrysanthemi in pH5.2 ~ 10.0 can grow at pH 6.0 to 8.4 between good growth, wherein the optimum growth pH of 6.8, when the pH value is less than 4.4 when bacteria stop growing. 5 through 9 different fungicides the base rot bacteria (Erwinia chrysanthemi pv.zeae) Toxicity Determination results show different pharmaceutical growth inhibitory effect of differences Bacteriostatic Wuningmeisu minimum effective concentration of 2.4μg/ml, best inhibitory effect. 70% streptomycin, bacteriostatic minimum effective concentration 70% Mn-Zn chlorothalonil were 58.30, and 81.40μg / m. 16% of the the triethyl aluminum phosphate, turpentine, acid copper also has some antibacterial effect. Thiazole zinc ceftiofur amide, 70% boutique A Tropsch WP, the killing Sanqian inhibitory effect of poor the antibacterial lowest effective concentration were 833.33,1156.63,562.20 and 595.74μg/ml.
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